incandescent
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C2 adjective /ˌɪnkænˈdɛsənt/

incandescent

白熱
Meaning
emitting light as a result of being heated; extremely bright or passionate
Example
The incandescent lamp lit up the entire hall.
白熱灯はホール全体を照らしました。
C1 adjective ˌɪn.trəˈspek.tɪv

introspective

内省的
Meaning
Characterized by or given to introspection; examining one's own thoughts and feelings.
Example
Writers tend to be highly introspective individuals.
作家はしばしば非常に内省的な人々である。
C1 verb /ˈɪtəreɪt/

iterate

反復する
Meaning
To repeat a process or statement, often to improve or refine.
Example
The software team will iterate the design until it meets user needs.
ソフトウェアチームは、ユーザーのニーズを満たすまでデザインを繰り返します。
C2 verb /ˈɪntərˌdɪkt/

interdict

禁じる
Meaning
to prohibit or forbid something by authoritative order, often by law or decree
Example
The court moved to interdict the sale of the illegal goods.
裁判所は違法な商品の販売を禁じることを決定しました。
A2 verb /ˌɪntrəˈduːs/

introduce

紹介する
Meaning
to present someone; to bring in for the first time
Example
Let me introduce you to my friend.
友達を紹介させてください。
C1 verb /ˌɪnstɪˈtjuːʃənəlaɪz/

institutionalize

制度化する
Meaning
to establish something as a formal institution, custom, or practice
Example
The government seeks to institutionalize environmental protection.
政府は環境保護を制度化しようとしています。
B2 noun /ɪmˈpeɪʃəns/

impatience

忍耐力不足
Meaning
The state of being quickly irritated or unable to wait calmly.
Example
His impatience grew as the meeting dragged on.
会議が長引くにつれて、彼の忍耐力不足が増しました。
B2 noun ɪnˌdʌstrɪəlaɪˈzeɪʃən

industrialization

産業化
Meaning
The development of industries in a country or region on a wide scale.
Example
Industrialization changed the global economy dramatically.
産業化は世界経済を劇的に変えました。
B2 adjective /ˌɪrɪˈzɪstəbəl/

Irresistible

抗し難い
Meaning
too attractive and tempting to be resisted; impossible to resist
Example
The chocolate cake was absolutely irresistible.
チョコレートケーキは絶対に抵抗できないほど魅力的だった。
B1 verb /ɪnˈvɛs.tɪ.ɡeɪt/

investigate

調査する
Meaning
to carry out a systematic inquiry to discover facts or information
Example
The police will investigate the incident thoroughly.
警察は事件を徹底的に調査するでしょう。
C1 verb /ɪmˈbɛd/

imbed

埋め込む
Meaning
To fix firmly or deeply in a surrounding mass.
Example
The journalist imbedded himself with the troops to report firsthand.
ジャーナリストは部隊に埋め込まれて、最前線から報告を行った。
B1 adjective /ɪnˈkrɛdəbl/

incredible

信じられない
Meaning
so extraordinary that it is hard to believe; amazing
Example
The view from the mountain was incredible.
山からの景色は信じられなかった。
C1 noun /ɪnˈɛk.wɪ.ti/

inequity

不平等
Meaning
Lack of fairness or justice; unequal distribution or treatment.
Example
Social inequity continues to be a global issue.
社会的不平等は依然としてグローバルな問題です。
B2 adjective ɪˈmɜː.sɪv

immersive

没入型
Meaning
Providing, involving, or characterized by deep absorption or immersion in something.
Example
Virtual reality creates an immersive learning environment.
仮想現実は没入型の学習環境を作り出します。
A2 adjective/noun /ˈɪndiən/

indian

インディアンの
Meaning
Relating to India, its people, or their culture.
Example
She loves Indian food, especially biryani.
彼女はインディアンの料理が好きで、特にビリヤニが好きです。
B2 verb /ˌɪntərˈfɪər/

interfere

幸せ
Meaning
to become involved in something that is not your concern; to hinder or obstruct
Example
Parents should not interfere in their children’s personal choices.
彼女は賞を受け取ったとき、自分の幸せを隠すことができませんでした。
A1 pronoun /ɪts/

its

それの
Meaning
Belonging to or associated with a thing previously mentioned.
Example
The company changed its logo last year.
会社は昨年そのロゴを変更しました。
C1 adjective ˌɪn.təˈstel.ər

interstellar

星間の、インターステラ、宇宙の
Meaning
Occurring or situated between stars.
Example
Scientists study interstellar travel possibilities.
科学者たちはインターステラ旅行の可能性を研究しています。
C1 adjective /ɪnˈses.ənt/

incessant

絶え間ない
Meaning
Continuing without pause or interruption; constant.
Example
The incessant noise from the construction site made it hard to concentrate.
建設現場からの絶え間ない騒音は集中するのを困難にしました。
C2 noun /ɪˈnænɪti/

inanity

馬鹿げたこと, 空虚
Meaning
a nonsensical remark or action; silliness; emptiness
Example
The speech was full of inanities that bored the audience.
スピーチは聴衆を退屈させる馬鹿げたことだらけだった。
A2 noun /ˈɪm.ɪdʒ/

Image

イメージ; 画像; 形象
Meaning
a representation of the external form of a person or thing in art; a mental picture or impression
Example
The company worked hard to improve its public image after the scandal.
企業はスキャンダル後、公共のイメージを改善するために一生懸命働きました。
C2 noun /ˌɪlɪbəˈræləti/

illiberality

不寛容
Meaning
The quality of being illiberal; lack of tolerance or generosity.
Example
The illiberality of the new laws alarmed the citizens.
新しい法律の不寛容が市民を驚かせました。
B2 noun /ɪnˈhæbɪtənt/

inhabitant

住民
Meaning
a person or animal that lives in a particular place
Example
The inhabitants of the village rely on farming for their livelihood.
村の住民は生活のために農業に頼っています。
C1 noun /ɪnˈdʌstriəsnəs/

industriousness

勤勉
Meaning
The quality of being hardworking and diligent.
Example
His industriousness earned him a promotion at work.
彼の勤勉さは、仕事で昇進をもたらしました。
C1 adjective /ˌɪnkəmˈpætəbl/

incompatible

互換性がない
Meaning
Not able to exist or work together without conflict.
Example
Their personalities were completely incompatible.
彼らの性格は完全に互換性がなかった。
C2 noun /ˌɪnədˈvɜːrtəns/

inadvertence

不注意
Meaning
Failure to pay attention; carelessness.
Example
The error happened through sheer inadvertence.
エラーは単なる不注意で発生しました。
C2 noun /ˌɪnvəˈkeɪʃən/

invocation

祈願
Meaning
the act of calling upon a higher power for help, blessing, or inspiration
Example
The ceremony began with an invocation to the gods.
儀式は神々への祈願から始まりました。
C2 noun /ˌɪdiəˈsɪŋkrəsi/

idiosyncrasy

特異性
Meaning
A distinctive or peculiar characteristic, habit, or mannerism unique to an individual.
Example
One of her idiosyncrasies was humming while working.
彼女の一つの特異性は、仕事中に口ずさむことでした。
C1 noun /ˌɪməˈtjʊərəti/

immaturity

未熟さ
Meaning
the state of not being fully developed emotionally, mentally, or physically; lack of maturity
Example
His immaturity made it difficult for him to handle responsibility.
彼の未熟さは責任を果たすことを難しくした。
C1 adjective /ɪnˈdʌldʒənt/

indulgent

寛容な
Meaning
Having a tendency to be overly generous or lenient with someone.
Example
The indulgent mother allowed her child to stay up late.
寛容な母は子供を遅くまで起きていることを許しました。
C2 adjective /ɪnˈkɒntɪnənt/

incontinent

失禁
Meaning
lacking control over urination or defecation; lacking self-restraint
Example
The patient was incontinent after surgery.
手術後、患者は失禁していた。
B1 noun /ɪnˈvɛstər/

investor

投資家
Meaning
a person or organization that puts money into financial schemes, property, or business ventures with the expectation of achieving a profit
Example
The investor funded the startup with a large sum of money.
投資家はスタートアップに大金を投資しました。
B1 verb ɪnˈvɛst

invest

投資する
Meaning
To put money, effort, time, etc. into something to make a profit or get an advantage.
Example
Investing in intellectual property can generate passive income.
知的財産への投資はパッシブインカムを生み出す可能性があります。
C2 noun /ˌɪkθiˈɒlədʒɪst/

ichthyologist

魚類学者
Meaning
A scientist who studies fish.
Example
The ichthyologist discovered a new species of fish in the river.
魚類学者は川で新しい魚の種を発見しました。
B2 adjective /aɪˈrɒnɪkəl/

ironical

皮肉な
Meaning
expressing irony; having the nature of irony
Example
Her ironical tone made everyone uncomfortable.
彼女の皮肉な口調は、皆を不快にさせました。
C1 noun /ˌɪnklɪˈneɪʃən/

inclination

傾向
Meaning
A natural tendency or urge to act or feel in a particular way.
Example
She has an inclination towards helping others.
彼女は他の人を助ける傾向があります。
C2 adjective /ˌɪlˈneɪ.tʃəd/

ill-natured

性格が悪い
Meaning
Having a bad or unpleasant character; unkind or malicious.
Example
He made an ill-natured remark about his colleague.
彼は同僚について悪意のある発言をしました。
B2 verb ɪnˈvɛst.ɪŋ

investing

投資
Meaning
The act of putting money into financial schemes, shares, property, or a commercial venture with the expectation of achieving a profit.
Example
Investing in stocks can generate long-term wealth.
株式投資は長期的な富を生むことができます。
C1 adjective /ɪmˈpɜːrviəs/

impervious

透過しない
Meaning
Not allowing fluid to pass through; unable to be affected by something.
Example
The jacket is impervious to rain.
ジャケットは雨に透過しません。
B2 noun /ˈɪnvənˌtɔːri/

inventory

インベントリ
Meaning
A complete list of items, such as goods in stock or property.
Example
The shopkeeper checked the inventory before opening the store.
店主は店を開店する前にインベントリを確認しました。
C2 noun /ɪmˈpʌlʃən/

impulsion

Meaning
a strong urge or drive to act; the act of impelling
Example
His impulsion to travel made him leave his job suddenly.
B2 verb /ɪnˈdʌldʒ/

indulge

楽しむ
Meaning
to allow oneself to enjoy something enjoyable, often excessively
Example
He indulged in a piece of chocolate cake after dinner.
彼はディナーの後でチョコレートケーキの一切れを楽しんだ。
C1 adjective /ɪnˈtrɛpɪd/

intrepid

勇敢な
Meaning
fearless and adventurous, often used humorously
Example
The intrepid traveler explored the jungle alone.
その勇敢な旅行者は一人でジャングルを探検した。
C2 adjective /ˌɪrɪˈprəʊtʃəbl̩/

irreproachable

非の打ち所がない
Meaning
Beyond criticism; faultless.
Example
The judge was known for his irreproachable integrity.
その裁判官は非の打ち所がない誠実さで知られていた。
B2 adjective /ɪnˈsɛnsətɪv/

insensitive

無神経な
Meaning
Showing or feeling no concern for others' feelings.
Example
His insensitive comment hurt her deeply.
彼の無神経なコメントは彼女を深く傷つけました。
A1 adjective /ɪmˈpɔː.tənt/

important

重要
Meaning
Of great significance or value; likely to have a profound effect on success, survival, or well-being.
Example
Important steps must be taken to address pollution.
汚染に対処するためには重要なステップを踏む必要があります。
B2 noun /ɪnˈvɒlvmənt/

involvement

関与
Meaning
the act of taking part in something
Example
His involvement in the project was crucial.
彼のプロジェクトへの関与は重要だった。
C2 adjective /ɪnˈsɛnʃənt/

insentient

無感覚の
Meaning
Lacking perception, consciousness, or sensation.
Example
The rock is an insentient object with no awareness.
岩は意識のない無感覚の物体です。
C1 noun /ˌɪndɪˈdʒɛstʃən/

indigestion

Meaning
Discomfort or pain in the stomach associated with difficulty in digesting food.
Example
He avoided spicy food because it often gave him indigestion.
C2 adjective /ˌɪndɪˈvɜːrtɪbəl/

indivertible

Meaning
Not able to be turned aside or diverted.
Example
The judge's indivertible attention was on the case.
C2 adjective /ɪnˈseɪʃiət/

insatiate

飽くなき
Meaning
impossible to satisfy; always wanting more
Example
He had an insatiate desire for power.
彼は権力への飽くなき欲望を持っていた。
C2 noun /aɪˈdɒlətri/

idolatry

偶像崇拝
Meaning
The worship of idols or extreme admiration for someone or something.
Example
The priest condemned the idolatry practiced in the village.
司祭は村で行われている偶像崇拝を非難した。
C2 verb /ˈɪŋkʌlpeɪt/

inculpate

非難する
Meaning
To blame or accuse someone of wrongdoing.
Example
The evidence seemed to inculpate the suspect in the crime.
証拠は容疑者を犯行に巻き込んでいるように見えた。
C2 adjective /ɪmˈplækəbl/

implacable

容赦しない
Meaning
unable to be appeased, calmed, or pacified
Example
The soldiers faced an implacable enemy who refused to surrender.
兵士たちは降伏を拒否した容赦しない敵に直面した。
C1 noun /ˈɪnˌmeɪt/

inmate

囚人
Meaning
a person confined to an institution such as a prison or hospital
Example
The prison has over a thousand inmates.
刑務所には千人以上の囚人がいます。
C1 noun /ˌɪm.pəˈzɪʃ.ən/

Imposition

課税; 負担; 不公平な要求
Meaning
the action or process of imposing something or of being imposed; an unfair burden or demand
Example
The imposition of new taxes without consultation angered the citizens greatly.
相談なしに新しい税金が課され、市民は非常に怒りました。
B1 verb /ɪnˈsɪst/

insist

主張する
Meaning
to demand firmly; to state persistently
Example
He insisted on paying the bill.
彼は請求書の支払いを主張しました。
C2 verb /ɪmˈpɛnd/

impend

迫る
Meaning
to be about to happen; to loom threateningly
Example
Dark clouds suggested that a storm was impeding.
暗い雲が嵐が迫っていることを示唆していた。
C2 adjective /ɪmˌpɜːrˈsweɪdəbl/

impersuadable

説得できない
Meaning
not able to be convinced or persuaded
Example
She remained impersuadable despite all our arguments.
彼女はすべての議論にもかかわらず説得できなかった。
B1 noun /ɪnˈtɛnʃən/

intention

意図
Meaning
A plan, aim, or purpose behind an action.
Example
Her intention was to finish the project before the deadline.
彼女の意図はプロジェクトを締め切り前に終わらせることだった。
C2 adjective /ˌɪrɛvəˈrɛnʃəl/

irreverential

無礼な
Meaning
Showing a lack of respect for things that are generally taken seriously.
Example
His irreverential humor often shocked traditional audiences.
彼の無礼なユーモアはしばしば伝統的な観客を驚かせました。
C1 adjective /ɪˈmuː.və.bəl/

immovable

動かせない
Meaning
Not able to be moved; fixed in position.
Example
Immovable barriers prevent change.
動かせない障害物が変化を妨げる。
C2 adjective /ɪnˈsɛptɪv/

inceptive

初期の
Meaning
Relating to or marking the beginning or initial stage of something.
Example
The inceptive phase of the project was marked by enthusiastic planning.
プロジェクトの開始段階は熱心な計画で特徴づけられました。
B2 noun ˌɪmplɪmenˈteɪʃən

implementation

実行
Meaning
The process of putting a decision or plan into effect; execution.
Example
Proper implementation of policies is crucial.
方針の適切な実行は重要です。
C2 verb /ɪˈnjʊər/

inure

慣れる
Meaning
To become accustomed to something, especially something unpleasant.
Example
Soldiers quickly became inured to the harsh conditions.
兵士たちはすぐに過酷な状況に慣れました。
C1 adjective /ˈɪmpətənt/

impotent

無力
Meaning
Lacking power, ability, or strength to take effective action.
Example
The citizens felt impotent against the corrupt system.
市民は腐敗したシステムに対して無力だと感じた。
C1 verb /ɪnˈkrɪmɪˌneɪt/

incriminate

有罪にする
Meaning
to make someone appear guilty of a crime or wrongdoing
Example
The new evidence could incriminate the suspect in the robbery case.
新しい証拠がロビー事件の容疑者を有罪にする可能性があります。
C2 verb /ɪmˈbruː/

imbrue

汚す
Meaning
To stain, especially with blood.
Example
His hands were imbrued with blood after the battle.
戦いの後、彼の手は血で汚れていた。
A1 pronoun /aɪ/

i

私
Meaning
used by a speaker to refer to himself or herself
Example
I am learning English every day.
私は毎日英語を学んでいます。
C1 adjective /ɪmˈpɛtʃ.u.əs/

impetuous

衝動的な
Meaning
Acting or done quickly and without thought or care; impulsive.
Example
His impetuous decision led to unexpected consequences.
彼の衝動的な決断は予想外の結果を招いた。
B2 adjective ɪnˈev.ɪ.tə.bəl

inevitable

避けられない
Meaning
Certain to happen; unavoidable.
Example
Death is an inevitable part of life.
死は人生の避けられない一部です。
C1 verb /ɪmˈploʊd/

implode

内爆
Meaning
To collapse or burst inward violently.
Example
The old building imploded during the demolition.
古い建物は解体中に内向きに崩壊しました。
C1 noun /ɪnˈfɜː.mə.ti/

Infirmity

虚弱; 病気; 衰弱
Meaning
physical or mental weakness; a disease or ailment; frailty
Example
Despite his advanced age and various infirmities, he remained mentally sharp and alert.
高齢で多くの病気を抱えていても、彼は精神的に鋭く、警戒心を持ち続けました。
B2 noun ˌɪm.plɪˈkeɪ.ʃən

implication

含意
Meaning
A conclusion that can be drawn from something although it is not explicitly stated; a likely consequence.
Example
The implication of climate change is severe.
気候変動の含意は深刻です。
C1 adjective /ɪmˈpɜːmiəbl/

impermeable

不透水の
Meaning
Not allowing fluid or gas to pass through.
Example
The container is made of impermeable plastic.
その容器は不透水のプラスチックでできています。
C2 noun /ɪmˈpjuːɪsəns/

impuissance

無力, 無能
Meaning
inability to take effective action; helplessness
Example
The government’s impuissance in the face of crisis frustrated the people.
危機の前で政府の無力さが人々を失望させた。
C2 adjective /ɪˈrɛfrəɡəbəl/

irrefragable

反論できない
Meaning
Impossible to refute, deny, or break
Example
The lawyer presented irrefragable evidence that proved his client’s innocence.
弁護士は彼のクライアントの無実を証明する反論できない証拠を提示しました。
B2 noun /ˈɪntərfeɪs/

interface

インターフェイス
Meaning
a point where two systems, subjects, or organizations meet and interact
Example
The user interface is designed to be intuitive and user-friendly.
ユーザーインターフェイスは直感的で使いやすく設計されています。
C1 verb /ɪmˈpɛrɪl/

imperil

危険にさらす
Meaning
To put in danger or at risk.
Example
Reckless driving can imperil the lives of others.
無謀な運転は他人の命を危険にさらす可能性があります。
C2 adjective /ˌɪnkɔːrˈpɔːriəl/

incorporeal

無形
Meaning
lacking a physical body; not composed of matter; intangible
Example
Ghosts are often described as incorporeal beings.
ゴーストはしばしば無形の存在として描かれます。
B2 adjective /ˈɪrɪteɪtɪd/

irritated

いらいらした
Meaning
feeling annoyed or impatient; having inflamed or sore physical condition
Example
She felt irritated by the constant noise outside her window.
窓の外の絶え間ない騒音に彼女はいらいらした。
C2 adjective /ˌɪnɪkˈstɛnsəbl/

inextensible

伸縮不可
Meaning
Not capable of being stretched or extended.
Example
This rope is made of an inextensible material.
このロープは伸縮不可の材料でできています。
B2 adjective /ˌɪnsɪɡˈnɪfɪkənt/

insignificant

重要でない
Meaning
Too small or unimportant to be worth considering.
Example
The cost was so insignificant that nobody noticed it.
そのコストは重要でなく、誰もそれに気づかなかった。
C1 noun /ˈɪnkjʊˌbeɪtər/

incubator

インキュベーター
Meaning
a device or environment that provides suitable conditions for eggs, cells, or infants to develop
Example
The premature baby was placed in an incubator for care.
未熟児はケアのためにインキュベーターに入れられました。
C1 noun /ɪnˈkɜːrʒən/

incursion

侵入
Meaning
A sudden attack or invasion into a place or territory.
Example
The army repelled the enemy incursion at the border.
軍隊は国境で敵の侵入を撃退した。
C1 noun /ˌɪnkjʊˈbeɪʃən/

incubation

卵、細胞、または生物を適切な条件で発展させるプロセス
Meaning
the process of keeping eggs, cells, or organisms in the right conditions for development
Example
The incubation of the eggs lasted for three weeks.
卵のインキュベーションは三週間続きました。
C2 adjective /ˌɪnɪkˈspiːdiənt/

inexpedient

不適切
Meaning
Not advisable, suitable, or practical in the circumstances.
Example
It would be inexpedient to invest without proper research.
適切な調査なしで投資することは不適切です。
B2 noun /ɪnˈveɪʒən/

invasion

侵略
Meaning
An instance of invading a country, region, or personal space with armed force or unwelcome presence.
Example
The army prepared for the possibility of an invasion.
軍隊は侵略の可能性に備えました。
C2 noun /ɪˈrɛvərəns/

irreverence

不敬
Meaning
a lack of respect for people or things that are generally taken seriously
Example
His jokes about religion showed irreverence to the sacred traditions.
宗教についての彼の冗談は、神聖な伝統に対する不敬を示していました。
C2 verb /ɪnˈdɛmnɪfaɪ/

indemnify

Meaning
to compensate someone for harm or loss; to secure against future damage or cost
Example
The insurance company agreed to indemnify the client for the damages.
C2 adjective /ɪmˈpruːdənt/

imprudent

不注意な
Meaning
Not showing care for the consequences of an action.
Example
It was imprudent to drive in such stormy weather.
こんな嵐の天気で運転するのは不注意だった。
C2 noun /ˈaɪ.kɒn/

ikon

宗教的な画像やシンボル
Meaning
A religious image or symbol, especially in the Eastern Orthodox Church.
Example
The church displayed a beautifully painted ikon of the Virgin Mary.
教会は美しく描かれた聖母マリアのアイコンを展示しました。
C1 verb /ɪnˈsaɪt/

incite

扇動する
Meaning
to provoke; to stir up
Example
His speech incited the crowd to violence.
彼のスピーチは群衆を暴力に駆り立てた。
C2 noun /ˈɪntərˌloʊpər/

interloper

干渉者
Meaning
A person who becomes involved in a situation or place where they are not wanted.
Example
He felt like an interloper at the private family gathering.
彼はプライベートな家族の集まりで干渉者のように感じた。
C1 adjective /ɪˈnɛpt/

inept

不器用
Meaning
lacking skill or ability; clumsy or incompetent
Example
His inept handling of the situation made it worse.
彼の不器用な状況の対処が状況を悪化させた。
C1 verb /ɪnˈfɛst/

infest

侵入する
Meaning
to overrun in large numbers, especially so as to cause damage or discomfort
Example
The old house was infested with rats.
古い家はネズミで侵されていました。
C2 noun /ˌɪmprəˈpraɪəti/

impropriety

不正行為
Meaning
Failure to observe standards of honesty or modesty; improper behavior.
Example
The politician was accused of financial impropriety.
その政治家は財政的不正行為で告発されました。
C2 adjective /ˌɪnˈekspɜːrt/

inexpert

未熟な
Meaning
not skilled or experienced; lacking expertise
Example
The inexpert handling of the machine caused several mistakes.
機械の未熟な扱いがいくつかのミスを引き起こした。
B2 adjective /ˈɪn.tɪ.mət/

Intimate

親密な; 個人的な; 詳細な知識
Meaning
close in friendship; private and personal; detailed knowledge
Example
They have an intimate friendship that has lasted for decades.
彼らは何十年にもわたる親密な友情を持っています。
C1 noun ɪnˈsɛpʃən

inception

始まり
Meaning
The establishment or starting point of an institution or activity.
Example
The inception of the company marked a new era in the industry.
その企業のインセプションは業界に新しい時代を築きました。
C2 noun /ˈɪntərˌveɪl/

intervale

川沿いの低地、通常は肥沃で平坦
Meaning
A low-lying tract of land along a river, usually fertile and flat.
Example
The farmers cultivated crops on the lush intervale by the river.
農民たちは川沿いの肥沃な土地で作物を育てた。
C2 noun /ˌɪmbəˈsɪləti/

imbecility

愚かさ
Meaning
Extreme foolishness, stupidity, or weakness of mind.
Example
The plan was abandoned due to its sheer imbecility.
その計画はその愚かさから放棄されました。
C2 noun /ˌɪnəməˈrɑːtə/

inamorata

Meaning
A woman with whom someone is in love; a female lover.
Example
He wrote a poem dedicated to his inamorata.
C2 adjective /ˌɪnˌɑːpərˈtuːn/

inopportune

タイミングが悪い瞬間
Meaning
Happening at a bad or inconvenient time.
Example
His call came at the most inopportune moment.
彼の電話は最もタイミングが悪い瞬間にかかってきた。
C1 noun /ˈɪn.trə.vɜːrt/

introvert

内向的
Meaning
A person who tends to be shy and prefers spending time alone rather than in groups.
Example
As an introvert, he preferred reading over attending parties.
内向的な性格として、パーティに参加するよりも読書の方が好きでした。
B2 verb /ɪnˈstrʌkt/

instruct

指示する
Meaning
to teach; to give directions
Example
The teacher instructed the students carefully.
先生は生徒に注意深く指示しました。
C2 adjective /ˈɪnfəntaɪl/

infantile

幼稚な
Meaning
characteristic of an infant; childish
Example
His infantile behavior embarrassed everyone at the meeting.
彼の幼稚な行動は会議でみんなを困らせた。
B2 adjective /aɪˈrɒnɪk/

ironic

皮肉な、風刺的な
Meaning
happening in the opposite way to what is expected, often amusing or sarcastic
Example
It is ironic that the fire station burned down.
消防署が焼けるのは皮肉です。
C2 adjective /ɪnˈɛstɪməbl/

inestimable

計り知れない
Meaning
Too great or valuable to be measured or estimated.
Example
Her contribution to the project was of inestimable value.
プロジェクトへの彼女の貢献は計り知れない価値があった。
B2 verb /ɪnˈveɪd/

invade

侵入する
Meaning
to enter a place or country forcefully, especially as an enemy
Example
The army invaded the neighboring country.
軍隊は隣国に侵入しました。
C2 verb /ɪˈmjʊər/

immure

閉じ込める
Meaning
to confine or enclose someone against their will
Example
The prisoner was immured in a dark cell.
囚人は暗い監房に閉じ込められた。
C2 verb /ˈɪmprɛɡneɪt/

impregnate

妊娠させる / 飽和させる
Meaning
To make pregnant; to fill or saturate with something.
Example
The scientist used a method to impregnate the material with resin.
科学者は樹脂で素材をインプレグネイトする方法を使用しました。
C1 noun /ɪnˈsɒm.ni.ə/

Insomnia

不眠症
Meaning
habitual sleeplessness; inability to sleep; the condition of being unable to sleep
Example
Her chronic insomnia made it difficult for her to concentrate during work hours.
彼女の慢性的な不眠症は、仕事中に集中するのを難しくさせた。
C1 verb /ɪnˈklaɪn/

incline

傾く
Meaning
to feel willing or favorably disposed toward something; to bend or tilt
Example
She is inclined to agree with the proposal.
彼女は提案に賛成する傾向があります。
B2 noun /ɪnˈkluːʒən/

inclusion

インクルージョン
Meaning
the action or state of including or being included within a group or structure
Example
Diversity and inclusion are key values in modern workplaces.
多様性とインクルージョンは現代の職場における重要な価値観です。
C1 adjective ˌɪn.təˈmɪt.ənt

intermittent

断続的
Meaning
Happening irregularly, not continuously.
Example
The rain was intermittent throughout the day.
雨は一日中断続的でした。
C2 adjective /ˈɪndələnt/

indolent

怠惰
Meaning
Wanting to avoid activity or exertion; lazy.
Example
The indolent cat slept in the sun all afternoon.
怠惰な猫は午後ずっと太陽の下で寝ていました。
C1 adjective /ɪnˈsɛp(ə)rəbəl/

inseparable

切り離せない
Meaning
Unable to be separated or always together.
Example
The two friends have been inseparable since childhood.
二人の友達は子供の頃から切り離せないです。
C1 verb /ɪˈnɔːɡjʊreɪt/

inaugurate

Meaning
To formally begin or introduce something, especially with a ceremony.
Example
The mayor will inaugurate the new bridge tomorrow.
C1 noun /ɪnˈhɛrɪtər/

inheritor

相続人
Meaning
a person who receives money, property, or a title when someone dies
Example
She became the inheritor of her family's estate.
彼女は家族の財産の相続人となった。
C2 adjective /ˌɪnsəˈpɔːrtəbl̩/

insupportable

耐えられない
Meaning
Too extreme or difficult to be endured.
Example
The heat was insupportable during the long journey.
長い旅の間、暑さは耐えられなかった。